Combo Ribociclib & Letrozole Tx Examined for Breast CA Survival Duration
HealthDay News — Ribociclib plus letrozole is associated with significantly longer progression-free survival for patients receiving initial systemic treatment for hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer, according to a study published online October 8 in the New England Journal of Medicine. The research was published to coincide with the annual European Society of Medical Oncology Congress, held from October 7 to 11 in Copenhagen, Denmark.
Gabriel N. Hortobagyi, MD, from the University of Texas MD Anderson Cancer Center in Houston, and colleagues conducted a randomized phase 3 trial to examine the efficacy and safety of ribociclib combined with letrozole for first-line treatment. Participants included 668 postmenopausal women with HR-positive, HER2-negative recurrent or metastatic breast cancer. Patients were randomized to receive either ribociclib plus letrozole or placebo plus letrozole. After 243 patients had disease progression or died, a planned interim analysis was performed.
The researchers found that the duration of progression-free survival was significantly longer in the ribociclib versus the placebo group (hazard ratio, 0.56). The median follow-up duration was 15.3 months. The progression-free survival rate was 63.0 and 42.2% in the ribociclib and placebo groups, respectively, after 18 months. The overall response rate was 52.7 and 37.1%, respectively, for patients with measurable disease at baseline (P<0.001).
"The duration of progression-free survival was significantly longer among those receiving ribociclib plus letrozole than among those receiving placebo plus letrozole, with a higher rate of myelosuppression in the ribociclib group," the authors write.
The study was funded by Novartis, the manufacturer of ribociclib and letrozole.